I wouldn't use hard pipe for the drains. You may want to move them from time to time. I would use flexible pool hose for the drains.
I would also use flexible hose for the return(s) to cut down head loss.
I suggested a 40 breeder because of the footprint. It's 36 x 18. You will have many more skimmer options if you go with a wider tank as a sump.
One more thing I would suggest- if you haven't purchased this display yet, I would seriously consider a 180. A 150 is only 18" front to back, a 180 is 24. You will love the extra depth. Plus, a 180 is a few inches shorter top to bottom than a 150, which makes it much easier to reach the bottom, with light, and your arm.